1. Field of the Invention
The present invention relates to a sound data processing apparatus for reading sound data stored in an external memory to process the read sound data.
2. Description of the Related Art
In recent years, a sound data processing apparatus for reading sound data stored in an external memory, such as a flash memory, by connecting the external memory to the apparatus, and for performing decoding processing and the like for the read sound data, has been widely used.
The configuration of a related art sound data processing apparatus 100 is shown in FIG. 3. The sound data processing apparatus 100 includes a central processing unit (CPU) 10, a decoder 12, an interface unit (IF unit) 14, and a NOR-type flash memory 16. A NAND-type external memory 102, such as a flash memory, is detected by the CPU 10 by connecting the external memory 102 to the IF unit 14.
The CPU 10 reads a driver for accessing the external memory 102, the driver being stored in the flash memory 16, and accesses the external memory 102 by means of the driver. That is, the CPU 10 reads the sound data stored in the external memory 102 in advance through the IF unit 14 on the basis of an instruction by a user or the like, and transfers the read sound data to the decoder 12 at predetermined timing. The decoder 12 decodes the sound data transferred from the CPU 10 in accordance with a predetermined format, and outputs the decoded sound data as an audio output.
Moreover, the technique of providing an audio system compatible with a multi-codec coping with a plurality of audio codecs was disclosed. The technique was also disclosed that used a CPU to judge whether an audio codec program stored in a RAM incorporated in a digital signal processing unit (DSP) was compatible with music information to be decoded by the digital signal processing unit or not, and that changed the processing of the program according to the compatibility.
Now, various types of NAND-type external memories 102 have been developed in recent years. It is necessary to store numerous drivers compatible with respective types of external memories 102 in the flash memory 16 in advance in order to cope with the various external memories 102. The memory capacity of the flash memory 16 should accordingly be enlarged with every increase in the types of external memory 102.